Anterior Segment Optical Coherence Tomography Angiography Assessment of Corneal Vascularisation After Combined Fine-Needle Diathermy with Subconjunctival Ranibizumab: A Pilot Study

Introduction: To describe anterior segment optical coherence tomography angiography (AS-OCTA) imaging to monitor corneal vascularisation (CoNV) and scar reduction after combined fine-needle diathermy (FND) with subconjunctival ranibizumab. Methods: Prospective clinical study of six eyes from six subjects with corneal scar and CoNV which underwent combined FND with subconjunctival ranibizumab. All eyes were imaged using slit-lamp photography (SLP) and AS-OCTA (Optovue, Inc., Fremont, CA, wavelength: 840 nm) before and after the operation, with two independent masked assessors analysing all images. Main outcome measures were changes in median corneal scar area and vessel density (AS-OCTA) comparing pre- and postoperative imaging up to month 3 and 6. Results: The mean age of the subjects was 60 ± 23 years, with three males and three females. CoNV and corneal scarring involving the visual axis were present in all eyes, secondary to previous infective keratitis (n = 3), severe blepharokeratoconjunctivitis (n = 2), or chemical injury (n = 1). Follow-up time frame ranged from 2 to 6 months postoperation. There was a reduction in median corneal scar area from 30.2 mm² (IQR 18.7–38.5) before surgery to 14.8 mm² (IQR 7.1–19.6) after surgery, with a median reduction of 37.1% (IQR = − 3.1–86.9, p = 0.046). There was also a reduction in median cornea vessel density (AS-OCTA) from 20.8% (IQR 16.1–20.8) before surgery to 17.6% (IQR 14.0–17.6) after surgery, with a median reduction of 15.1% (IQR 13.2–15.1, p < 0.001). Conclusions: Combined imaging of SLP and AS-OCTA is useful for monitoring treatment response of corneal scarring and CoNV after combined FND with subconjunctival Ranibizumab.